As an environmentally friendly building material, recycled pervious concrete can not only alleviate the increasingly severe urban flooding and heat island effect, but also realize the resource utilization of construction waste. However, the porous nature of recycled pervious concrete leads to its low strength, and there is an urgent need to develop recycled pervious concrete with good mechanical and permeability properties. This paper proposes to mix fly ash and basalt fibers in the waste brick aggregate pervious concrete, and investigate the effects of mixing fly ash and basalt fibers on the properties of recycled brick pervious concrete by comparing the mechanical properties, water permeability and frost resistance of recycled brick pervious concrete. The results show that: with the increase of fiber admixture, the mechanical properties and frost resistance of recycled brick-mixed permeable concrete are improved, and the water permeability is decreased; fly ash is more obvious to improve the late strength of recycled brick-mixed permeable concrete, with the increase of fly ash admixture, the mechanical properties and frost resistance of recycled permeable concrete are improved, and the water permeability is decreased, and the excessive admixture of fly ash will greatly reduce the water permeability of recycled brick-mixed permeable concrete. Excessive incorporation of fly ash will greatly reduce the water permeability of recycled pervious concrete. Under the premise of better water permeability and mechanical properties, the optimal mix combination of 10% fly ash and 0.05% basalt fiber was selected on the basis of 85% recycled concrete aggregate and 15% brick aggregate as the mixed coarse aggregate.

In recent years, coastal reclamation has become an important way for coastal areas to ease the contradiction between supply and demand along the land and to develop and utilize marine resources. However, large-scale coastal reclamation will change the original natural properties of the sea area and cause changes in the surrounding hydrodynamic environment. Although coastal geomorphic features have a non-negligible impact on tidal energy loss and disaster prevention, few studies have paid attention to the intrinsic connection between the complexity of coastal morphology and the rate of tidal reduction. In this study, Hangzhou Bay is selected as the research object, and a model based on the correlation between coastal geomorphic complexity and tidal energy reduction rate is constructed by using the fractal geometry theory and the quantitative evaluation method of landscape complexity, and the model is used in the assessment of the impacts of reclaimed land in Zhoushan Islands on the geomorphic complexity and tidal energy dissipation. The results of the study show that the differential tide reduction rate is highly correlated with the complexity of islands, shoreline irregularities, curved boundaries and spatial morphology. In the application of the model, it was found that the traditional planning and design of reclamation led to a dramatic change in shoreline morphology, and with the significant reduction of the number of subdimensions D and the shape index S, the differential tidal reduction rate would be reduced by more than 88%, which also poses a significant threat to coastal and downstream estuarine bay disaster prevention. Finally, based on the above analysis, effective control indexes and scientific reclamation measures are proposed to provide theoretical basis for the efficient utilization and protection of mudflats in China.

As an important part of the construction industry, rural residential buildings are characterized by low energy utilization, unreasonable structures and low consumption levels, and it is particularly important to study their low-carbon transformation and evaluation system. In view of the many low-carbon transformation needs of rural residential buildings, the existing research results were analyzed in depth, and the coefficient of variation method was used to identify the important factors affecting the low-carbon transformation of rural residential buildings, and the evaluation system of rural residential buildings’ low-carbon transformation was determined by Analytic Hierarchy Process (APH), and the system was used in a rural residential building low-carbon evaluation study. The results show that the influence of “energy use”, “envelope structure” and “economic factors” on the decarbonization of buildings is obvious, with the weights of 36.4%, 24.5% and 19.5% respectively. Among the secondary indicators, “clean energy utilization”, “electricity consumption”, “external wall insulation system” and “window performance” are the most important factors in reducing carbon emissions in rural areas. The most critical influencing factors for the low carbonization level of clean energy in rural residential buildings are “window performance”. Finally, based on the constructed low carbonization evaluation system, we propose a targeted solution strategy to provide a theoretical basis for the establishment of an effective low carbonization evaluation system for clean energy in rural residential buildings.

Coastal reclamation can provide new space for agriculture, industry and urbanization, as well as new investment opportunities in coastal areas. As a result, both the length and proportion of artificial shoreline increased significantly. Meanwhile, the complexity of coastal morphology will be diminished by large-scale land reclamation. Although coastal geomorphic characteristics has a crucial impact on tidal energy loss and disaster prevention, little research has been conducted on the relationship between the tidal range reduction rate and coastal morphological complexity. This relationship is essential for predicting the impact of coastal complexity changes caused by accelerated land reclamation on tidal energy loss. Taking Hangzhou Bay and Zhoushan Islands as the research objects, combined with fractal geometry theory and quantitative assessment method of landscape complexity, the correlation between coastal geomorphological complexity and tidal distance reduction rate is analyzed, and A model based on the correlation of the tidal range reduction rate and geomorphological complexity is established. The model is applied to evaluate the effect of reclamation in Zhoushan Islands on the landscape complexity and dissipation of tidal energy. The results show that the tidal range reduction rate is reduced with the decrease of fractal dimension and shape index, indicating that the coastal geomorphologic complexity has an important effect on tidal energy loss. The efficient control indicators and scientific reclamation measures are discussed in this paper. This study provides new ideas for the analysis of the comprehensive impact of reclamation on coastal geomorphic characteristics and disaster prevention, and can provide guidance for the efficient utilization and protection of tidal flats.